Valve for gas heating systems.



N. WIPARK. VALVE FORGAS HEATING SYSTEMS.

APPLICATION FILED NOV. 24. 1917.

1,302,841 Patented May 6, 1919..

3 SHEETS-SHEET l- N. W. PARK. VALVE FOR GAS HEATING SYSTEMS.

APPLICATION FILED NOV. 24. 19!?- Patented. May 6, 1919. 3 SHEETS-SHEET 2 FIG mun/0., WASHINIJIUN. v c

. N. W. PARK.

VALVE FOR GAS HEATING SYSTEMS.

APPUCATION HLED NOV. 24, I911.

Patented Mayfi, 1919.

3 5HEETS-SHEET 3 Imi 7 u. 4 1 VV UNITED STATES PATENT OFFICE.

NICHOLAS W. PARK, OF BROOKLYN, NEW YORK, ASSIGNOR TO GENERAL. FIRE EXTINGUISHER COMPANY, OF PROVIDENCE, RHODE ISLAND, A CORPORATION OF NEW YORK.

VALVE FOR GAS HEATING SYSTEMS.

Specification of Letters Patent.

Patented May 6, 1919.

Application filed November 1917. Serial No. 203,740.

To all whom it may concern Be it known that I, NICHOLAS vV. PARK, a citizen. of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented new and useful Improvements in Valves for Gas Heating Systems and the like, of which the following is a specification.

- This invention relates to improvements in valves for gas heating systems and the like. More particularly it has been designed for use in connection with a system of heating in which the combustion of the gas is carried on within a chamber or burner box and artificial suction .is employed to take away the products of combustion, drawing them through a radiator, water heater or other means for extracting the heat of combustiou therefrom on their way to the place of exhaust. In such systems it is customary to place several radiators or other devices having burners on a system of piping served by a single suction fan, some of which burners may be in use and others not, but all of which contain constantly burning pilot lights. The admission of gas may be efiected by a valve, opened and held open by the main suction whenever means, automatic such as a thermostat or otherwise, signify that more heat is required. Such a gas valve closes if the suction ceases, as by stoppage of the fan; but no means has been known to shut the gas valve automatically in case the air supply ceases, or is unduly diminished while the suction continues good. Some times a gas valve at an improper time admits gas into the system, whence it may escape with objectionable results. One cause may be that accumulations of dust, drawn in with the current of air, have settled upon the burner or upon the gas valve or elsewhere. Hence screens are used, at the air entrances; but then the dust gradually gathers on the screen and finally may clog it so that the air current is reduced and the working of the apparatus deranged. In such a case the continued suction by the fan may hold the gas valve open although the supply of air for combustion of the gas thus admitted is shut off or reduced.

It is an object of the present invention to provide so that any closure of the air screen, or, broadly, any shut off or undue reduc effect, which holds many dilferent tion of the air supply, must result in the automatlc closing of the gas valve; and to do this notwlthstandlng the somewhat contrary I fact that in normal operation some retardation' of the air supply is necessary, enough to produce the partial vacuum, or su ction the gas valve open. The ob ectstated is attained by providing the usual suction tube, into which both air and gas are drawn and wherein they are mixed, and by arranging a diaphragm or float, whose movement opens and closes the gas valve, with its inner side-exposed to the suction, and with its outer side exposed to air outside of the suction tube but within the screen through which the air is drawn. In the particular embodiment. of the invention which is here illustrated as a preferred form, the screen serves as the entrance to a chamber in which one side of the dia phragm is exposed, from which chamber the suction tube draws its supply of air through a restricted passage. The other side of the diaphragm is exposed to a more direct effect of the suction. The air capacity of the screen is sufficiently great, and the passage from the chamber beyond it to the tube is sufficiently restricted so that the air intervening between the screen and the said restricted passage is normally of a pressure which is practically atmospheric pressure. It is to this pressure that the outer side of the diaphragm is exposed; and this pressure is needed for holding the gas valve open. Hence when the screen becomes clogged, so that the suction of the tube reduces the pressure of air in the screened chamber, such reduction of pressure on the outside of the diaphragm permits the gas valve to close automatically. Closure also occurs if the suction ceases, in which case atmospheric pressure reaches the inner side of the diaphragm, thus with equal effectiveness destroying the differential of pressure on the A diaphragm. Details of construction are set forth hereinafter.

As the invention may be embodied in forms within the appended claims, the patent is not to be limited to the particulars of construction here specifically represented. It is intended to cover, by proper expression int-he appended claims,

whatever features ofpatentable novelty exist a in the invention disclosed. In the accompanying drawings Figure 1 is an elevation, in section on a vertical medial'plane through apparatus embodying the invention;

Fig. 2 is a plan of part of the same appa- I ratus in section on the line 2-2 of Fig. 1;

through another modification,

Fig. 3 is a plan of the same in section on the "line'3-'3 of Fig. 1;

Fig. 4c is a plan of the same in section on the line 4-4: of Fig. 1;

Fig. 5 is an elevation of a modification, in medial section, corresponding to Fig. 1;

Fig. 6 is a similar view of a modification of adetail; and

Fig. 7 is an elevation of the exterior of the'forms shown in Figs. 1-4.

Figs. "8 and 9 are sectional elevations respectively on medial planes at right angles to each other. i

The drawings are somewhat in the nature of diagrams; obvious parts being omitted for the sake of clearness and convenience in describing the particular features which are new.

Referring tothe drawings, and particularly to the three styles illustrated in Figs. 1-7, 10 indicates a suction and mixing tube, through which air and gas flow in the direction of the arrow, toward a burner. The burner is not shown, nor the suction producing means beyond it, which may be of any suitable type such as a suction fan. A gas supply entrance 11, and an air supply entrance 12 are provided in the valve body. From the entrance 11 the gas passes into a chamber around the gas valve 14:, formed by a removable hood 11. For control of the gas, a ball 14 arranged over a valve seat 15 constitutes a valve for-closing the supply of gas, and has a stem 16 extending centrally downward to a float or diaphragm. (three forms of which are 20-2020) capable of lifting it. When the Valve 14: is raised, gas passes down through the seat 15 to the chamber 23 below whence it is drawn off through the suction and mixing tube 10. The stem 16 eXtends down through this chamber to the diaphragm 202020 and a screw nut 21 which is attached thereto for structural convenience and for adjusting. The diaphragm, which has to be relatively large in order to control the valve lt adequately, may be of any suitable type. In Fig. 1 it is represented as being of leather or metal or other material fastened at its periphery to a flange 50 within the enlarged part 13 of the body of the device. The diaphragm has its upper side consequently exposed to the pressure conditions of the suction and mixing tubelO, which are normally sub atmospheric, and its lower side to the pressure conditionsof air in the chamber 32.

The entrance 12 and the screen 30 are large enough so that air in the air chamber 32 is normally at atmospheric pressure or near it, notwithstanding constant draft of air therefrom through the passage 34 and around the diaphragm to the suction and mixing tube 10. In the passage is a regulator 33 which as illustrated in Figs. 1 and 1 consists of a butterfly valve fitted into the passage 34L for the purpose of restricting that passage to any desired degree, and thus regulating the quantity of air to be admitted to the mixing tube 10, and also regulating the degree of vacuum at the mixing tube.

As the gas valve is controlled directly by the diaphragm, the provision for operating it at will, or automatically as by a thermostat, consists in means for changing the conditions affecting the diaphragm. Such means are indicated by the butterfly valve 42 in the air inlet 12. The various parts are constructed of such weight and dimensions that when the normal suction exists in the mixing tube 10, and the normal pressure within the chamber 32, being practically atmospheric pressure, the differential of pressure acting on the diaphragm is enough to raise it, its stem 16 raising the valve 14- and thus admitting gas to the tube 10. The suction meanwhile is drawing air through the passage 3 1; and the operation of mixing air and gas is proceeding normally in tube 10. If the valve 42 be turned so that no air can enter through the passage 12 the difference between pressure above and below the diaphragm becomes so greatly reduced that the weight of the parts closes the valve 14 by gravity, thus shutting off gas in the normally operative manner. The suction, as caused by a constantly operating fan at a distance, continues unaltected by the opening or closing of the gas valve, or by movements of the diaphragm. Hence whenever by hand or by automatic control the entrance 12 is opened again, the diaphragm, being again subjected to the differential of pressure, is actuated thereby to open the valve 14; and, as the air passage 84 has remained partially open, the mixture of gas and air is made and moves on through the tube 10 to the burner where it is ignited by the constantly burning pilot light. Ordinarily the regulating valve 33 will be adjusted and set in proper position when the apparatus is originally installed.

As air is being constantly drawn in, while the suction continues, whether or not gas also is entering and being burned, the screen 30 is liable in time to become clogged, so that proper and complete combustion may not occur. Such clogging, by its very existence, permits the suction through passage 34: to reduce the pressure in the air chamber 32. When reduced enough, the diflerential of pressure on the diaphragm that is holding the gas valve open is enough diminished so that the weight of the parts pulls the diaphragm down, thus letting the gas valve 14 close. The supply of gas is thus shut off automatically when the air flow ceases or is too much reduced. This is a safety device, and is also a signal for the user to clean the screen.

The provision of a structure in which this principle can be recognized makes possible a very simple controller, and an arrangement by which the apparatus safeguards itself if it is allowed to run too long without needed attention. The controller by which the gas is normally turned on or off is represented at 42 only diagrammatically, and may in practice take various forms some of which embody more or less complication of structure, delicacy of lit and expense for machine work in manufacture, the main idea being to control the differentials of pressure on the diaphragm; and this does not necessarily involve shutting off the air supply. The invention permits it to be embodied in a main air valve at the entrance 12, as shown in Figs. 1 and 5. As there represented, a butterfly valve 42 being a simple stamping or casting, balanced and moving with negligible friction on hardened pin and cup bearings 40, is actuated by hand or by a thermostatically controlled magnet (not shown in the drawing) in the usual way through a link 42. This controls the inflow of air to chamber 32, through the entrance 12. So longas it remains closed the usual volume of air is excluded from the screen 30, and hence the screen clogging process, which otherwise would continue uninterruptedly whether the gas burner were in use or not, ceases so long as the burner is not in use. As a slight flow of air will do no harm, the valve need not fit tightly; from which it follows that it can be made to work with little friction, and that its cost of construction can be reduced by the resulting simplification. Another embodiment of the invention, in simplified form, i shown in Fig. 5 where a float 20 is shown. This is a simple disk, which may be of aluminum, fiber, or other material, depending by a stem 16 from the ball gas valve 14 in a well whose diameter slightly exceeds its own, allowing sufficient clearance for its free movement up and down. Its upper side is exposed to the subatmospheric pressure of the suction and mixing tube. Air, entering through the screen 30 at opening 12 with suflicient freedom to maintain atmospheric pressure normally in the chamber 32, holds up the float 20, becausethe flow of air around the edges of the float 20 to the other side of the float is not at a suflicient rate to prevent the maintenance of a partial vacuum above the float. Air also may be drawn through an opening 34 and regulating valve 33 asin Fig. 1, into the mixing tube 10, if such are provided. If so, the valve 33 is set so nearly closed that the air flow is small and the partial vacuum above the float is not thereby broken when the entrance 12 is open. In this case the passage 34 becomes a by-passage. Gas enters as before through the passage 11, and through valve 14 when open. When the screen 30 becomes clogged or the valve 42 is closed, so that the suction makes the pressure subatmospheric in chamber 32, the float 20' and valve 14 fall, shutting ofl the gas.

If the proper relation between the pressures on opposite sides of the float is provided there is no need for the passage 34 and regulating valve 33. A a commercial measure the proper size for the float and for the passage around or through it may be determined by experiment for known suction and gas conditions. When so determined, apparatus suitable for those conditions may be made without provision for adjustment. In that case the apparatus may be selected from stock according to the conditions where it is to be installed. In this type provision should be made to prevent the float 20 from closing off all flow of air from the lower to the upper side of the diaphragm. Such means is indicated in the drawing by protuberances 51 which intervene between the float and its seat. These may be tacks or screws, or mere elevations in the material composing the float or its seat. An alternative form having some advantages is illustrated in Fig. 6, where the float 20 is adapted to be seated against the flange 50, but has holes 52- which are continuously open in such size and number as will permit flow of air to the proper degree to accomplish the two objects of supplying all that is needed for combustion and of maintaining a difference of pressure on opposite sides of the float. The workman installing the apparatus in that case need carry only one size of float; and he can drill as many holes as are requisite for the proper adjustment.

In Figs. 8 and. 9 another embodiment of the invention is shown, With a body 13 having a mixing chamber 10 a gas inlet port 11, and air inlet through a large exterior screen 30. The restricted passage 84 for air entering the body 13* opens from within the metal screen 30" which is of such large size and of such shape as to make three sides of a diaphragm chamber 32. The gas port 11 leads into a chamber 53 within which is a ball valve 14 adapted to close upon the up per end of a tube 54, through which, when open, gas reaches chamber 10 by passing through. upper ports 55 in the sides of said tube, whose height in the body can be ad justed by a screw nut 71. At its lower end the tube 54 is interiorly threaded and so holds the upper end of a tubular nipple 56 that extends down from the interior of body 13 to where it holds the upper section 58 of a sheet metal housing which with its removable lower section 59 incloses the diaphragm 20*. This housing is inclosed by the screen 30 and has an opening at some convenient place, represented at the middle of its bottom 59, so that air within the housing corresponds in pressure to other air within the screen, except such air as is within the diaphragm 20, as hereinafter explained. The upper portion of the housing is clamped down by a nut 57. The valve 14* has a stem 16 hanging down within the tube 54 and holding threaded upon it a weight 60 with check nut 61. The height of the weight can be adjusted at will to cooperate with the head on the upper end of thediaphragm spindle 62, within the nipple, whose lower end is screwed through a collar 63,, that is part of the lower diaphragm wall, and a weight 21 The said diaphragm, which as a whole is marked 20 corresponding to the parts 20' and 20 of other figures, is of bellows type, having an upper wall 66 perforated opposite the open end of nipple 56, to which it is soldered, its upper and lower walls being joined at a peripheral ring 65. The lower wall is iinperforate. Through the nipple 56, leakage around the loose fitting spindle 62, and'lower ports 55, there is communication between the interior of the diaphragm and the suction chamber 10"-. Hence under ordinary operating conditions air is slowly drawn from the interior of the diaphragm, causing it to collapse, with its bottom portion moving upward, under the superior pressure of exterior air above and belo it, within the housing 58, 59, which pres ure is the same as that of air elsewhere within the screen. This raises the spindle 62 and the parts 60,16, and 14 admitting gas. If the air within the diaphragm were to approach equality of pressure with the air outside of it, whether by increase of its own pressure, or by decrease of pressure of air within the screen to sub-atmospheric pressure approximating that within the suction chamber, the differential of pressure upon the diaphragm would cease, or be reduced, so that the weight of the diaphragm and the associated weight 21 would draw down the spindle 62 to the position illustrated in Fig. 8, thus letting the gas valve 14* be closed. The restriction in the main passage by which air reaches the suction chamber is controlled by a valve or part which serves the function of the part 33 in Fig. 1, but in form has a cylindrical body 67 with a circumferential slot 68, which can, by the flanged head 69, be adjusted about the 'aXis of the fastening screw 70 to increase or reduce the opening .34. The screw 7 0 holds the flanged head 69 of this valve seated against the body 13 Ordinarily it will be set permanently, after being once properly adjusted, because other means is provided for service use in destroying at will the differential of pressure on the diaphragm.

The service control of the gas valve. in the apparatus illustrated in Figs. 8 and 5) is effected by means of a by-passage, 73, 72, from within the screen to the interior of the diaphragm, controllable by a valve of suitable type, herein shown a plug valve 7-1- turning in the chamber so as to connect or disconnect the passages 73, 72. \Vhen connected, as illustrated in Fig. 9, the differential of pressure between the inside and outside of the diaphragm is destroyed. Such relatively little draft of air into the suction chamber as occurs around the loose fitting spindle 62 is insufficient to reduce pressure within the diaphragm. Hence the pa its fall, letting gas valve 14 close. Turning the valve 74: so as to disconnect the passages 73, 72, leaves the passage 72 without a supply of air. The suction operating in chamber 1O then soon withdraws air from the diaphragm, which thereupon collapses, lifting and opening the gas valve 14". If, however, the screen 3O becomes suflicicntly clogged at. any time, the presence of the passages 73. 72, whether connected or disconnected, will not prevent an establishment of a uniformity of pressure within and without the diaphragm. thus leading to the closure of valve 14.

The elements of Figs. 1, 5, 6 and 8, respectively referred to above as diaphragm and float are in the claims which follow covered by the more comprehensive term vane, it being obvious that the functioning of this element does not depend on whether the restricted passage for air is an attenuated peripheral opening, or is a passage elsewhere, either nearby or even directly through the element. The important point is that the vane controls the gas valve according to balance of air pressure upon its opposite sides. Obviously this vane might be variously constructed or mounted without departing from the principle of the invention. The phrase superior pressure, in the claims, signifies excess over the pressure acting on the other side of the vane.

Although the term suction chamber is used, such being the style and name commonly used in the trade, signifying a reduction below atmospheric pressure, producing a draft, it is evident that the apparatus would be applicable if the air were supplied under greater than atmospheric pressure, and that the flow of air toward any region of lower pressure is equally in that case an illustration of suction. or draft. In theclaims the word suction chamber is to be understood in this broader significance, the comparison being between the pressure of air supplied and the pressure within. As the connection from the diaphragm may be at a place where mixture has already occurred, the term gaseous pressure is used, applying whether the gas be air, or the hydrocarbon, or a mixture.

I claim as my invention l. A mixing device for air and gas, comprising in combination a passage for air having an. entrance portion with contents normally continuously at a superior pressure, a mixing portion with contents normally at an inferior pressure and a restriction between the two portions, normally dividing the two said regions of pressure; a gas inlet to the mixing portion; a vane aving one side exposed to the gaseous pressure in the entrance portion of the passage and its other side exposed to gaseous pressure in the same passage beyond the restriction; and means by which movement of the vane controls the gas inlet.

2. A mixing device for air and gas, comprising in combination a passage for air having an entrance portion with contents normally continuously at a superior pressure, a mixing portion with contents normally at an inferior pressure and a restriction between the two portions, normally dividing the two said regions of pressure; a gas inlet to the mixing portion; a vane having one side exposed to the gaseous pressure in the entrance portion of the passage and its other side exposed to gaseous pressure in the same passage beyond the restriction; another air passage, and means to control it, leading from the region of said superior pressure to the side of the vane which is toward said inferior pressure and sufficiently large to approximately destroy the difference of pressure between the two sides of the vane; means by which movement of the vane controls the gas inlet; the whole being arranged for the vane to be in position holding the gas inlet closed in the absence of said difference of pressure.

3. A mixing device for air and gas, comprising in combination a passage for air havlng an entrance portion with contents normally continuously at a superior pressure, a mixing portion with contents nor mally at an inferior pressure and a restriction between the two portions, normally dividing the two said regions of pressure; a gas inlet to the mixing portion; a vane having one side exposed to the gaseous pressure in the entrance portion of the passage and its other side exposed to gaseous pressure in the same passage beyond the restriction; and means by which movement of the vane controls the gas inlet; and means whereby the difference of pressure on said vane may 'be varied.

4:. A mixing device for air and gas, comprising in combination a passage for air having an entrance screen exposed to the atmosphere, and beyond that an entrance por tion with contents normally continuously at atmospheric pressure, beyond that a restriction, and beyond that a portion where the air is normally at a lower pressure; a vane having one side exposed to the pressure in said entrance portion, and another side exposed to the pressure in said portion beyond the restriction; a gasinlet to the passage beyond said restriction; and means by which movement of the vane let.

5. A mixing device for air and gas, comprising in combination a passage for air hav ing an entrance portion with contents normally continuously at a superior pressure, a mixing portion with contents normally at an inferior pressure, and a restriction be tween the two portions, normally dividing the two said regions of pressure; a gas inlet to the mixing portion; a vane having one side exposed to the gaseous pressure in the entrance portion of the passage and its other side exposed to gaseous pressure in the same passage beyond the restriction; a strut extending from the vane through part of the passage having the lower pressure, and a valve thereon at a fixed distance from the vane and adapted to close the gas inlet; the whole being arranged for the action of gravity on the valve to draw it toward its seat, and for the superior pressure on the side of the vane which is toward the entrance portion of the passage to oppose said effect of gravity, and normally to overcome it.

6. The combination, with a passage wherein gas and air are mixed, of an inlet for gas to the latter part of the passage, and an impedable entrance to the passage for incoming air, there being a restriction in the air passage, between the entrance portion and the place where gas is admitted, sufficient to make a difference of gaseous pressure in the passage; and means exposed to the air pressure both before and after the restriction and operated by said difference of pressure, closing the gas inlet when the pressures in the two portions of the air passage before and after the restriction become nearly the same.

7. The combination. with a passage wherein gas and air are mixed, of an inlet for gas to the latter part of the passage, and an impedable entrance to the passage for incom ing air, there being a restriction in the passage, between the entrance portion and the place where gas is admitted, sufiicient to make a difi'erence of gaseous pressure in the passage; and means exposed to and operated by said difference of pressure, closing the gas inlet when the pressures in the two portions of the passage before and after the restriction become nearly the same; there being a by-passage with valve from before the restriction to the side of said means which is beyond the restriction, whereby the differcontrols said gas in ence of pressure on said means can be substantially eliminated.

8. An automatic gas controlling apparatus comprising the combination of acasing having means for the introduction of gas and air and their admixture and for Withdrawal of the mixed product, by suction a gas valve; means for dividing the air passage leading from the entrance to the place of mixture into a zone normally of atmospheric pressure and a zone normally Copies of this patent may be obtained for of sub-atmospheric pressure, ada ted for either to extend into the place of t ie other under abnormal conditions; and means operated by the difference of gaseous pressure between said two zones to hold said gas ,valve open, and to permit it to close when the said gaseous pressures approach a condition of balance.

Signed by me at Providence, R. 1., this 20 19th day of November 1917.

NICHOLAS W. PARK.

five cents each, by addressing the Commissioner of Patents. Washington, D. O. 

